A study published this week by Washington State University
research professor Charles Benbrook finds that the use of herbicides in the
production of three genetically modified herbicide-tolerant crops - cotton,
soybeans and corn - has actually increased. This counterintuitive finding is
based on an exhaustive analysis of publicly available data from the U.S.
Department of Agriculture's National Agriculture Statistics Service. Benbrook’s
analysis is the first peer-reviewed, published estimate of the impacts of
genetically engineered (GE) herbicide-resistant (HT) crops on pesticide use.
In the study, which appeared in the open-access,
peer-reviewed journal Environmental Sciences Europe, Benbrook writes that the
emergence and spread of glyphosate-resistant weeds is strongly correlated with
the upward trajectory in herbicide use. Marketed as Roundup and other trade
names, glyphosate is a broad-spectrum systemic herbicide used to kill weeds.
Approximately 95 percent of soybean and cotton acres, and more than 85 percent
of corn, are planted to varieties genetically modified to be herbicide
resistant.